While acyl halide compounds such as benzene-1,3,5-tricarboyl trichloride and adipoyl dichloride are readily soluble in a variety of hydrocarbon and halogenated hydrocarbon solvents, their hydrolyzed and partially hydrolyzed analogs (3,5-bis(chlorocarbonyl)benzoic acid and 6-chloro-6-oxohexanoic acid) are only slightly soluble, e.g. less than 0.02 wt. %. As a consequence, it is difficult to prepare in-situ solutions of such hydrolyzed reaction products in a hydrocarbon or halogenated hydrocarbon solvent. Nevertheless, hydrocarbon and halogenated hydrocarbon solutions including such hydrolyzed reaction products would be useful in a variety of applications including the preparation of polyamides. U.S. Pat. No. 5,736,371 describes a process for preparing succinic acid monochloride. Marvel, et al., Journal of Organic Chemistry, vol 18, no. 12, (1953) 1664-1669 describes a process for preparing p-chloroformylbenzoic acid.